Abstract

In a printer in which character code bytes representing characters to be printed are translated into graphic code bytes, assembled into lines and pages, and thereafter used to select character image bits which are applied to modulate a scanning laser beam and thereby effect printing of the characters, the pitch of each character is determined independently of other characters in each line being printed by pitch bits included in the sets of character image bits. As each scan line of modulation bits from a set of character image bits is selected for use in modulating the laser beam, the pitch bit included within the bits is examined to determine whether the width of the charactor is to be a maximum or some value less than the maximum. For the maximum width all of the modulation bits are applied to modulate the laser beam, while for a character cell width less than the maximum, only a selected number of the modulation bits are used to modulate the laser beam. An oscillator maintains a constant clock rate for the system as it defines modulation periods for the individual bits, while associated timing circuitry controls the serial flow of selected modulation bits to modulate the laser beam as well as the successive addressing of the different graphic code bytes in the line being printed.